The present invention relates to seat frames for automobiles, and more particularly to such a frame having an optional "all-belts-to-seat" design.
The physical characteristics of automobile seating and safety belt assemblies are in large part regulated by a set of national safety standards designed to protect a passenger from injury during collision. When designing seating and restraint systems, reducing cost and weight also are desirable. In addition, each line of seats must be designed to conform to the size and shape requirements of the particular vehicle. These variations in size and shape typically require a separate frame design for each seat, which is expensive and time-consuming.
There is a growing trend to provide automotive seating with integral safety belts. This type of design, commonly referred to as all-belts-to-seat, eliminates the need for separate passenger restraint systems. Instead, a complete seat and safety belt assembly meeting national safety standards can be installed together.
One all-belts-to-seat design is disclosed in U.S. Pat. No. 5,253,924, issued Oct. 19, 1993, to Glance. The Glance seat incorporates a reinforcing beam added to the seat back frame to support the safety belt shoulder harness above the passenger's shoulder and to transfer crash forces to the frame of the seat. Reinforcing beams add undesired weight to the seat assembly and also create an unattractive asymmetric seat profile.
Another all-belts-to-seat design is disclosed in U.S. Pat. No. 5,123,673, issued Jun. 23, 1992, to Tame. The belt retractors are mounted to an upper portion of the seat back frame. Such a construction requires an extremely strong seat back frame that can bear the crash forces imparted by a loaded passenger restraint system.
In addition, current all-belts-to-seat designs include a single-height safety belt terminal, which can not be adjusted to match the height of the occupant. This reduces the effectiveness of the safety belt and may even pose a safety hazard. For example, a terminal location that is too low may result in potentially injurious downward force being applied to a passenger's shoulder during collision. While a terminal location that is too high may be uncomfortable or result in unwanted play in the belt.